SAN FRANCISCO -- Mortality associated with hepatitis C has surpassed that of HIV, a researcher said here.

Action Points

Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.

Explain that a CDC review of death certificate data from 1999 through 2007 found that mortality due to hepatitis C virus (HCV) has risen dramatically, overtaking deaths due to HIV in 2006.

Note that most of the deaths occurred among middle-age individuals and that the investigators suspected that the numbers might be an underestimate due to lack of diagnosis of HCV in all patients.

SAN FRANCISCO -- Mortality associated with hepatitis C has surpassed that of HIV, a researcher said here.

The declining death rate from HIV crossed the rising rate associated with hepatitis C infection in about 2006, according to Scott Holmberg, MD, of the CDC.

On the other hand, the rate of deaths associated with hepatitis B has been relatively flat, Holmberg reported at the annual meeting of the American Association for the Study of Liver Diseases.

The finding, from an analysis of death statistics from 1999 through 2007, comes as another study presented here suggested that as many as 800,000 new cases of hepatitis C could be diagnosed under a proposed new screening approach.

Indeed, Holmberg told an oral session here that the figures he and colleagues turned up are probably underestimates of the mortality burden of viral hepatitis in the U.S., partly because many people with viral hepatitis have yet to be diagnosed.

The issue also arises with HIV, he noted, but current estimates are that about 20% of those with HIV in the U.S. are not yet diagnosed. For hepatitis C, he said, the rate of diagnosis is probably less than half of those who actually have the virus.

The researchers looked at 21.8 million death certificates from the National Center for Health Statistics. Deaths were defined as being related to one of the three viruses if they were listed as either underlying or contributing causes of death.

Those data were used to construct the temporal trends, Holmberg said. The researchers also analyzed data for 2007 to get a picture of cause and variables associated with the incidence and prevalence of the diseases.

Holmberg reported that the rate of deaths related to hepatitis B was almost constant over the study period, at less than one per 100,000 people. In 2007, for instance, there were 1,815 such deaths.

On the other hand, he said, deaths associated with hepatitis C increased significantly, with a yearly age-adjusted mortality rate change of plus 0.18 deaths per 100,000 people. The toll reached 15,106 deaths in 2007.

In contrast, HIV deaths fell to 12,734 in 2007, the researchers found.

The highest toll of hepatitis deaths was among the middle-aged – those 45 through 64.

Holmberg reported that 59% of deaths related to hepatitis B occurred in that age group, as did 73% of the deaths linked to hepatitis C. In both cases, the rate was significantly higher than in the reference group – those 44 and younger.

For instance, just 8% of hepatitis C deaths occurred in the reference group, compared with 39% among those ages 45 through 54 and 34% among those 55 through 64.

As expected, coinfection with HIV significantly increased the risk of death from the hepatitis viruses, with adjusted odds ratios of 1.8 and 4.0 for hepatitis B and C, respectively.

But those risks paled compared with some other comorbidities. Specifically:

Having chronic liver disease led to an adjusted odds ratio for death of 32.1 for hepatitis B and 34.4 for hepatitis C, with the respective 95% confidence intervals from 31.0 to 38.1 and from 31.0 to 33.3.

Being coinfected with the other virus led to an adjusted odds ratio of between 29.9 and 31.5, depending on which virus was considered the primary cause of death.

Holmberg cautioned that death certificate data have some inherent limitations, including incomplete ascertainment of causes, misclassification, and missing data.

A key finding of the analysis is that most of the hepatitis deaths are occurring in people 45 through 64, according to AASLD president Jake Liang, MD, of the National Institute of Diabetes and Digestive and Kidney Diseases in Bethesda, Md.

The causes remain unclear, he told reporters, although one possibility is the "youthful indiscretions" of the Baby Boomers.

From a public health standpoint, he added, "this is a population we really need to be concerned with ... We really need to be more aggressive in identifying them and trying to treat them."

The analysis was supported by the CDC. The authors are employees of the agency.